In manufacturing semiconductor devices, for example, wire bonding is widely used to electrically connect electrodes on a semiconductor chip to electrodes on a substrate with wires. A wedge bonding system is known as a means of the manufacturing method of a semiconductor device. This system involves connecting a wire to a bonding target without forming any balls at the tip of the wire. In such a wedge-bonding system, the wire is connected between a first bonding point and a second bonding point. A portion of the wire extended from a tip of a bonding tool is then cut to form a wire tail at the tip end thereof for a subsequent wire bonding process. This wire tail is then bonded to the next first bonding point as it is, without performing a ball-formation step.
However, when the first bonding point is, for example, an electrode on a semiconductor chip, the tip of the wire tail bonded to the first bonding point might come into contact with an adjacent electrode or a passivation film on the semiconductor chip, thereby potentially causing damage or defect in the semiconductor chip.
To solve such problems, a method is proposed in which a member (die) for bending the tip of a wire tail in the upward direction is prepared separately from the bonding target, and then a bonding tool is moved over this member to thereby shape the wire tail before bonding to the first bonding point—as disclosed, for example, in Patent Document 1. However, the bonding tool must be moved to a position away from the bonding target every time the wire bonding is applied, which makes it difficult to achieve a simple and efficient manufacturing method. Alternatively, taking into consideration the fact that this kind of problem occurs only at the first bonding point, reverse bonding, which involves reversing the bonding order, can also be proposed to solve the problems. However, due to a limitation of the bonding order, this method does not have a high degree of flexibility in design of manufacturing methods for semiconductor devices.